Diabetic patients need to measure their blood sugar level on a regular basis to maintain a normal blood sugar level by injecting insulin, dieting and so forth based on the measured blood sugar level. Therefore, patients need to always carry measuring instruments and measure their blood sugar level by themselves on a daily basis. For that purpose, patients puncture the skin of their fingers and so forth using a puncturing apparatus and measure their blood sugar level by making blood exuding from the skin contact a blood sugar measuring device. Biological information, such as lactic acid, hemoglobin A1C and so forth, is measured using blood obtained by the puncturing apparatus as well as the blood sugar level.
Although a puncturing apparatus with a needle has grown popular today, the risk of infection and so forth has been regarded as important and therefore a puncturing apparatus having a laser puncturing device using laser light has been known. This conventional high-voltage generating circuit 1 that drives the conventional laser puncturing apparatus is configured by: switch 3 connected to battery 2; boost circuit 4 connected to this switch 3; capacitor 6 connected to the output of this boost circuit 4 and connected to flash lamp (used as an exemplary light source) 5a constituting laser puncturing device 5; trigger switch 7a that is connected to the output of boost circuit 4 and is operated by the patient to generate a trigger signal; and trigger circuit 7 connected to this trigger switch 7a, as shown in FIG. 1. This trigger circuit 7 is connected to trigger electrode 5b provided in flash lamp 5a. 
Here, a lithium-ion battery having an electromotive force of 3.7V is used as battery 2, and a capacitor of 300 μF is used as capacitor 6. Then, boost circuit 4 charges capacitor 5 with a charging current of 1.2 A, and laser puncturing device 5 has an oscillation voltage of 400 V and the minimum oscillation voltage of 300 V.
In this high-voltage generating circuit 1, an output current of battery 2 is inputted to capacitor 6 through boost circuit 4 and therefore capacitor 6 is charged. Along with charging to capacitor 6, the terminal voltage of capacitor 6 rises. By this means, the voltage applied across flash lamp 5a also rises.
The voltage applied across flash lamp 5a rises to the oscillation voltage (about 400 V) by charging for about seven seconds, and then, the patient turns on trigger switch 7a. Therefore, flash lamp 5a lights on, and this light energy 5d excites laser crystal 5e. Laser light 5f is emitted from laser crystal 5e, passes through lens 5g and then punctures skin 9. When skin 9 is punctured, blood 10 exudes from skin 9.
Here, Patent Document 1 and Patent Document 2 have been known as prior art document information relating to the invention of this application.
Patent Document 1: Japanese Patent Application Laid-Open No. 2003-38662
Patent Document 2: Japanese Patent Application Laid-Open No. 2004-195245